United States
Environmental Protection
Agency
Office of Radiation Programs
Eastern Environmental
Radiation Facility
P.O. Box 3009
Montgomery AL 36109
ORP/EERF-79-2
March 1979
Radiation
oEPA
The Eastern Environmental
Radiation Facility's
Participation in
Interlaboratory Comparisons
of Environmental Sample
Analyses
-------
EPA Review Notice
This report has been reviewed by the Environmental Protection Agency (EPA) and approved for publication. Approval
does not signify that the contents necessarily reflect the views and policies of the EPA, nor does mention of trade
names or commercial products constitute endorsement or recommendation for use.
-------
Technical Note
ORP/EERF-79-2
The Eastern Environmental Radiation Facility's
Participation in Interlaboratory Comparisons
of
Environmental Sample Analyses
R. L. Blanchard
A. B. Strong
R. Lieberman
C. R. Porter
Eastern Environmental Radiation Facility
Office of Radiation Programs
U.S. Environmental Protection Agency
P. O. Box 3009
Montgomery, Alabama 36109
March 1979
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Radiation Programs
Eastern Environmental Radiation Facility
Montgomery, Alabama 36109
-------
PREFACE
The Easjern Environmental Radiation Facility (EERF) participates in the identification of
solutions to problem areas as defined by the Office of Radiation Programs. The Facility
provides analytical capability for evaluation and assessment of radiation sources through
environmental studies, surveillance, and analysis. The EERF provides technical assistance to
the State and local health departments in their radiological health programs and provides
special analytical support for Environmental Protection Agency Regional Offices and other
federal government agencies as requested.
In carrying out the responsibility mentioned above, a great number of environmental
analyses were conducted to determine the final results. To assure the accuracy and precision
of these results, the EERF has maintained an extensive quality assurance program both
intra- and intercomparison at the national and international levels.
It is our intention in this report to present our laboratory results in these programs during
the 8-year period that we have been part of the Environmental Protection Agency.
We concur with other investigators who feel that all laboratory quality assurance results
should be public record in order to encourage facilities with less stringent programs to
improve their performance. The most important functions of a quality assurance program are
to identify analytical problem areas and to maintain a continuous level of accuracy. It is
reasonably easy to achieve good results occasionally but much more difficult to maintain a
high degree of excellence continuously, and requires a great deal of effort and support from
everyone involved.
We feel that our results in this report are reasonably good, but we will strive to continue
improving them.
It is the intent of the EERF to issue brief biannual reports similar to this which will present
the results of our continuing participation in intercomparison programs.
We wish to thank those involved in the preparation and handling of these intercomparison
samples and we encourage their continuation.
Charles R. Porter
Director
Eastern Environmental Radiation Facility
in
-------
I. Introduction
For more than 10 years the Eastern Environmental Radiation Facility (EERF), Office
of Radiation Programs (ORP), U.S. Environmental Protection Agency (EPA), has
participated with other laboratories in intercomparing results of analyses for
radionuclides in environmental and biological samples through programs sponsored by
several agencies. The results of these intercomparisons are routinely published by the
Reference Center of the sponsoring agency. To identify the participating laboratories, a
code is used that is known only to the respective laboratory and Reference Center.
Therefore, the quality of a laboratory's performance is unknown to the other participants
and to the industry.
Whether this system of identification is appropriate or impedes improved laboratory
performance was the topic of a presentation at a recent conference (1). It was the author's
conjecture that laboratory performance should be public record in order to encourage
poorer quality laboratories to improve their performance to an acceptable level. As a
result, the Environmental Measurements Laboratory (EML), formerly the Health and
Safety Laboratory (HASL), published the results of their participation in the International
Atomic Energy Agency (IAEA) intercomparison program (2). As this laboratory has
similar convictions, this report presents the results of EERF's participation in
intercomparison programs with the EPA National Quality Assurance Program at the
Environmental Monitoring and Support Laboratory Las Vegas (EMSL-LV), the World
Health Organization (WHO), and the International Atomic Energy Agency.
Results are reported for the period 1970 to 1978. Records for prior years have not
been maintained at the laboratory, and some records for this period have apparently been
lost. Hence, this report will include all data available to the authors. Also, it is not the intent
of this report to statistically evaluate the results or compare performance to that of other
laboratories. Rather, it is to present the data for public record with only a few brief
comments on the quality of the laboratory's performance.
II. Participation in the EMSL-LV Intercomparison Program
By far the most comprehensive intercomparison program has been conducted with
the EMSL-LV Reference Center, relative to numbers of samples, sample types and
radionuclides. Routine sample types and the radionuclides included in each were:
Water - 3H(46), 51Cr(27), 60Co(30), 65Zn(27), 89Sr(14), 90Sr(13), 106Ru(29), 134Cs(29),
137Cs(29), 226Ra(29), 239Pu(2), Gross Alpha (38), Gross Beta (38)
Milk - 89Sr(58), 90Sr(56), 131I(58), 137Cs(56), 140Ba(58), K(55)
Food - 89Sr(20), 90Sr(19), 131I(19), 137Cs(17), 140Ba(19), K(17)
Soil - 60Co(5), 106Ru(4), 134Cs(1), 137Cs(5), 239Pu(13)
Air filters - 239Pu(7)
The number of each type analysis is given in parentheses. The results of these
analyses with the known concentrations are presented in tables 1 thru 5. The results for a
few nonroutine analyses are given in table 6. To compare the values reported by EERF
with the known values supplied by the Reference Center, the EERF values were divided by
-------
Table 1. EMSL-LV Water Cross-Check Samples (pCi/&)
Date
1/70
7/70
9/70
1/71
3/71
5/71
7/71
9/71
1/72
3/72
7/72
2/73
3/73
4/73
5/73
6/73
7/73
8/73
9/73
11/73
12/73
1/74
3/74
11/73
1/74
3/74
5/74
EERF
Value
333,700
36,900
48,100
7,400
9,700
2,900
2,300
NR
7,900
27,600
259,200
1 ,467
2,133
1,633
2,866
NR
1,800
3,233
2,967
2,966
2,631
1 ,812
3,526
ND
ND
ND
NR
Known
Value
326,000
36,800
50,900
7,500
10,200
2,800
1 ,900
4,500
8,100
28,900
261,700
1,518
2,126
1,390
2,590
2,334
1 ,801
3,519
3,019
2,953
2,610
1,755
3,395
0
0
0
349
R
1.20
1.00
0.95
0.99
0.95
1.04
1.21
0.98
0.96
0.99
0.97
1.00
1.18
1.11
1 .00
0.92
0.98
1.00
1.01
1 .03
1 .04
-
Date
3H
5/74
8/74
10/74
12/74
2/75
6/75
8/75
10/75
12/75
2/76
4/76
6/76
8/76
10/76
12/76
2/77
Mil
6/77
8/77
10/77
12/77
2/78
4/78
4/76
6/76
8/76
10/76
EERF
Value
2,782
1,437
2,039
3,153
2,688
2,149
3,180
1,524
1,028
1 ,057
1 ,773
2,313
3,330
1,590
2,297
1,163
1,987
2,150
1,020
1,803
983
1 ,703
2,190
NR
< 30
< 30
NR
Known
Value
2,673
1,437
1,975
3,395
2,803
2,204
3,200
1,203
1,002
1,080
1,776
2,502
3,100
1 ,520
2,300
1 ,060
1 ,760
1,970
980
1 ,650
970
1 ,680
2,220
0
0
0
0
R
1.04
1.00
1.03
0.93
0.96
0.98
0.99
1.27
1.03
0.98
1.00
0.94
1.07
1.05
1 .00
1.10
1.13
1.09
1.04
1.09
1.01
1.01
0.99
-------
Table 1. (Cont'd.)
Date
8/74
10/74
12/74
2/75
4/75
6/75
8/75
10/75
12/75
9/71
1/72
3/72
11/73
1/74
3/74
5/74
8/74
10/74
12/74
2/75
4/75
6/75
8/75
10/75
EERF
Value
ND
ND
NR
NR
ND
ND
227
< 30
< 30
265
122
82
ND
ND
486
NR
ND
ND
NR
NR
466
381
341
294
Known
Value
0
0
0
0
0
0
255
0
0
279
137
96
0
0
490
0
0
0
478
437
425
350
307
271
Date
R
51Cr
12/76
2/77
4/77
6/77
8/77
10/77
0.89 12/77
2/78
4/78
60Co
0.95 12/75
0.89 2/76
0.85 4/76
6/76
8/76
0.99 10/76
12/76
2/77
4/77
6/77
8/77
1.10 10/77
1.09 12/77
1.11 2/78
1.09 4/78
EERF
Value
NR
NR
164
< 30
136
132
< 30
< 30
< 30
221
226
NR
55
45
NR
NR
NR
32
27
25
37
77
36
48
Known
Value
104
202
177
0
120
153
0
0
0
203
209
102
53
42
30
0
45
35
29
25
38
74
34
49
R
0.93
1.13
0.86
1.09
1 .08
1.04
1.07
0.91
0.93
1.00
0.97
1.04
1.06
0.98
-------
Table 1. (Cont'd.)
Date
11/73
1/74
3/74
5/74
8/74
10/74
12/74
2/75
4/75
6/75
8/75
10/75
12/75
2/76
1/70
7/70
9/70
1/71
3/71
5/71
7/71
1/70
7/70
9/70
1/71
3/71
EERF
Value
ND
425
ND
NR
ND
ND
NR
NR
504
336
275
286
212
450
17
0
21
34
0
9
18
57
19
31
£10
53
Known
Value
0
372
0
0
0
0
0
472
497
327
281
250
201
445
20
0
31
36
0
10
21
57
20
30
10
49
R
1.14
-_
1.01
1.03
0.98
1.14
1 .06
1.01
0.85
0.68
0.94
0.90
0.86
1.00
0.95
1.03
1.00
1.08
Date
65Zn
4/76
6/76
8/76
10/76
12/76
2/77
Mil
6/77
8/77
10/77
12/77
2/78
4/78
89Sr
9/71
1/72
3/72
7/72
8/77
1/78
5/78
90Sr
1/72
3/72
7/72
8/77
1/78
EERF
Value
NR
84
115
NR
NR
NR
53
78
29
52
202
25
60
37
36
22
59
14
24
13
85
61
26
9
36
Known
Value
100
79
111
58
102
37
50
74
29
53
192
29
59
44
50
25
62
14
25
16
77
60
25
10
31
R
1.06
1.04
1.06
1.05
1.00
0.98 '
1.05
0.86
1.02
0.84
0.72
0.88
0.95
1.00
0.96
0.81
1.10
1.01
1.04
0.90
1.16
-------
Table 1. (Conf d.)
Date
5/71
7/71
1/72
7/72
11/73
1/74
3/74
5/74
8/74
10/74
12/74
2/75
4/75
6/75
8/75
10/75
12/75
1/72
3/72
11/73
1/74
5/74
8/74
10/74
12/74
2/75
EERF
Value
16
28
356
271
ND
ND
ND
NR
429
ND
NR
NR
511
331
397
274
166
284
144
ND
ND
NR
ND
516
NR
NR
Known
Value
15
26
381
253
0
0
0
0
421
0
0
0
497
325
279
247
181
322
150
0
0
0
0
481
452
422
R
1.07
1.08
0.93
1.07
1.02
---
1.03
1.02
1.05
1.11
0.92
0.88
0.96
1.07
Date
90Sr
5/78
106Ru
2/76
4/76
6/76
8/76
10/76
12/76
2/77
4/77
6/77
8/77
10/77
12/77
2/78
4/78
2/76
4/76
6/76
8/76
12/76
llll
4/77
6/77
8/77
EERF
Value
28
355
NR
63
< 50
NR
NR
NR
65
44
49
75
151
< 35
95
227
NR
96
47
NR
NR
30
48
24
Known
Value
27
336
99
79
63
99
99
151
72
62
54
74
145
36
113
230
77
106
51
93
76
27
44
25
R
1.04
1.06
0.80
< e.79
0.90
0.71
0.91
1.01
1 .04
< 0.96
0.84
0.99
0.91
0.92
1.11
1.09
0.96
-------
Date
4/75
6/75
8/75
10/75
12/75
9/71
1/72
11/73
1/74
3/74
5/74
8/74
10/74
12/74
2/75
4/75
6/75
8/75
10/75
12/75
1/70
7/70
9/70
1/71
3/71
5/71
Table
EERF
Value
411
288
240
319
192
257
180
101
ND
ND
NR
ND
ND
NR
NR
454
366
299
256
149
3.3
4.3
2.3
1.2
4.5
1.4
1. (Cont'd.)
Known
Value
400
304
256
349
202
262
158
106
0
0
0
0
0
497
472
450
378
307
274
151
3.1
4.2
2.1
1.0
4.3
1.3
R
1.03
0.95
0.94
0.92
0.95
0.98
1.14
0.95
1.01
0.97
0.97
0.93
0.99
1.07
1.02
1.10
1.20
1.05
1.08
Date
13, Cs
10/77
12/77
2/78
4/78
2/76
4/76
6/76
8/76
10/76
12/76
2/77
4/77
6/77
8/77
10/77
12/77
2/78
4/78
226Ra
11/74
1/75
5/75
7/75
11/75
1/76
EERF
Value
32
44
52
78
363
NR
52
35
NR
NR
NR
30
38
17
25
44
< 10
< 10
6
20
12
8
6
11
Known
Value
30
45
52
74
361
301
53
30
49
101
39
21
33
15
25
46
0
0
4.9
19
12
8.1
5.1
10.4
R
1.07
0.98
1.00
1.05
1.01
0.98
1.16
1.42
1.15
1.13
1.00
0.96
1.22
1.05
1.00
0.99
1.17
1 .06
-------
Table 1. (Cont'd.)
Date
7/71
9/71
1/72
3/72
7/72
6/73
1/74
5/74
7/74
till
1/70
7/70
9/70
1/71
3/71
5/71
7/71
9/71
1/72
3/72
7/72
8/73
12/73
2/74
4/74
7/74
9/74
EERF
Value
0.6
5.5
4.2
2.1
8.1
16
17
11
5
3.8
36
3
3.4
8
6
10
7
10
19
16
13
2
ND
42
77
61
23
Known
Value
0.5
5.1
4.0
2.0
7.1
NR
16
10
5.1
3.9
54
5
3.1
11
7
15
11
24
39
38
19
0
0
51
95
75
25
R
1.20
1.08
1.05
1.05
1.14
1.06
1.10
0.98
0.97
0.67
0.60
1.10
0.73
0.86
0.67
0.64
0.42
0.49
0.42
0.68
0.82
0.81
0.81
0.92
Date EERF Known
Value Value
226Ra
5/76
7/76
12/76
3/77
6/77
9/77
12/77
3/78
239pu
1/78
Gross Alpha
3/75
5/75
7/75
9/75
11/75
1/76
3/76
5/76
7/76
9/76
11/76
1/77
3/77
5/77
7/77
9/77
11/77
7
14
10
3
13
5.4
3.4
10.7
6.1
1.6
25
33
77
0
26
19
39
15
9
5
14
9
7
NR
26
8
20
13.1
9.5
3.1
12
5.1
3.5
10.2
5.5
1.7
98
40
86
0
31
20
49
25
10
5
17
12
9
15
29
10
27
R
1.07
1.05
0.97
1.08
1.06
0.97
1.05
1.11
0.94
0.26
0.83
0.90
0.84
0.95
0.80
0.60
0.90
1.00
0.83
0.75
0.78
0.90
0.80
0.74
-------
Table 1. (Cont'd.)
Date
11/74
1/75
1/70
7/70
9/70
1/71
3/71
5/71
7/71
9/71
1/72
3/72
7/72
8/73
12/73
2/74
4/74
7/74
9/74
11/74
1/75
EERF
Value
47
12
23
13
17
29
20
35
20
37
49
47
33
19
29
30
180
111
73
61
96
Known
Value
50
25
18
9
21
30
15
39
21
39
54
50
32
23
29
24
190
103
77
51
95
R
0.94
0.48
1.28
1.44
0.81
0.97
1.33
0.90
0.95
0.95
0.91
0.94
1.03
0.83
1.00
1.25
0.95
1.08
0.95
1.20
1.01
Date
Gross Alpha
1/78
3/78
Gross Beta
3/75
5/75
7/75
9/75
11/75
1/76
3/76
5/76
7/76
9/76
11/76
1/77
3/77
5/77
1111
9/77
11/77
1/78
3/78
EERF
Value
NR
19
41
61
21
43
39
59
46
30
25
16
14
38
32
NR
9
45
37
NR
31
Known
Value
7
20
26
60
0
52
31
60
49
35
25
16
15
37
36
15
12
30
49
39
29
R
0.95
1.57
1.02
0.83
1.25
0.98
0.94
0.86
1.00
1.00
0.93
1 .03
0.89
0.75
1.50
0.76
1.07
ND Not detected
NR Not reported
R EERF value -=- known value
-------
Date
1/70
2/70
3/70
7/70
8/70
9/70
10/70
1/71
2/71
3/71
4/71
5/71
6/71
8/71
9/71
10/71
11/71
1/72
2/72
3/72
4/72
9/72
12/72
1/73
2/73
3/73
4/73
5/73
6/73
EERF
Value
0
28
4
0
25
5
29
15
38
0
31
10
0
55
0
117
13
0
0
48
41
0
0
3
ND
NR
0
ND
99
Known
Value
0
26
0
0
25
3*
34
20
41
0
36
10
0
49
0
118
11
0
0
50
42
0
2
2
0
98
2
0
127
R
1.08
1.00
0.85
0.75
0.93
0.86
1.00
1.12
0.99
1.18
0.96
0.98
0.78
Date
89Sr
7/73
8/73
9/73
11/73
12/73
2/74
4/74
7/74
9/74
11/74
1/75
3/75
5/75
7/75
9/75
11/75
1/76
3/76
5/76
7/76
9/76
11/76
1/77
3/77
5/77
7/77
9/77
11/77
4/78
. _ . '
EERF
Value
83
NR
NR
100
NR
57
168
146
149
165
0
0
0
0
0
0
134
116
37
NR
NR
NR
NR
NR
50
21
36
11
88
; . u
Known
Value
98
96
85
123
89
83
204
151
157
172
0
0
0
0
0
0
103
150
51
100
45
34
73
0
44
28
54
15
101
R
0.85
0.81
0.69
0.83
0.97
0.95
0.96
1.30
0.77
0.73
1.14
0.75
0.67
0.73
0.87
-------
Table 2. (Cont'd.
Date
1/70
2/70
3/70
7/70
8/70
9/70
10/70
1/71
2/71
3/71
4/71
5/71
6/71
8/71
9/71
10/71
11/71
1/72
4/72
9/72
12/72
1/73
2/73
3/73
4/73
5/73
6/73
7/73
EERF
Value
19
12
9
19
17
10
26
36
13
11
50
10
11
13
40
58
10
69
77
26
1.4
< 1
103
NR
133
86
73
66
Known
Value
20
12*
11*
20
16*
13*
28
37
12*
12*
51
10*
10*
13*
35
52
10*
66
84
27
1
1
99
135
120
91
82
65
R
0.95
1.00
0.82
0.95
1.06
0.77
0.93
0.97
1.08
0.92
0.98
1.00
1.10
1 .00
1.14
1.10
1.00
1.05
0.92
0.96
1.40
1.04
1.11
0.95
0.89
0.99
Date
90Sr
8/73
9/73
11/73
12/73
2/74
4/74
7/74
9/74
11/74
1/75
3/75
5/75
7/75
9/75
11/75
1/76
3/76
5/76
7/76
9/76
11/76
1/77
3/77
5/77
1111
9/77
11/77
4/78
EERF
Value
NR
NR
106
NR
204
166
122
120
92
74
48
23
91
148
71
101
51
137
< 2
28
21
28
21
10
26
49
21
12
Known
Value
158
72
135
103
198
172
152
124
102
75
50
25
97
151
75
100
50
154
0
30
16
24
18
10
25
51
20
9
R
0.79
1 .03
0.97
0.80
0.97
0.90
0.99
0.96
0.92
0.94
0.98
0.95
1.01
1.02
0.89
0.93
1.31
1.16
1.17
1.00
1.04
0.96
1.05
1.33
10
-------
Table 2. (Cont'd.
Date
1/70
2/70
3/70
7/70
8/70
9/70
10/70
1/71
2/71
3/71
4/71
5/71
6/71
8/71
9/71
10/71
11/71
1/72
2/72
3/72
4/72
9/72
12/72
1/73
2/73
3/73
4/73
5/73
6/73
EERF
Value
0
73
0
3
76
4
149
25
39
2
64
15
0
100
1
121
12
184
2
143
227
69
3
no
4
NR
126
.139
152
Known
Value
0
75
0
0
76
0
152
30
42
0
62
13
0
96
0
123
12
196
0
149
222
70
0
110
0
0
140
142
142
R
0.97
1.00
0.98
0.83
0.93
1.03
1 .15
1.04
0.98
1 .00
0.94
0.96
1.02
0.99
1.00
0.90
0.98
1.07
Date
I31J
7/73
8/73
9/73
11/73
12/73
2/74
4/74
7/74
9/74
11/74
1/75
3/75
5/75
7/75
9/75
11/75
1/76
3/76
5/76
7/76
9/76
11/76
1/77
3/77
5/77
7/77
9/77
11/77
4/78
EERF
Value
116
NR
NR
99
187
142
138
142
186
115
98
76
46
0
104
73
48
69
< 10
46
123
82
79
51
52
36
< 10
145
80
Known
Value
115
144
123
104
177
150
150
142
188
126
101
76
50
0
100
75
50
75
0
50
120
85
69
51
50
38
0
143
82
R
1.01
0.93
1 .06
0.95
0.92
1.00
0.99
0.91
0.97
1 .00
0.92
1.04
0.97
0.96
0.92
0.92
1.03
0.97
1.14
1 .00
1.04
0.95
1.01
0.98
11
-------
Table 2. (Cont'd.)
Date
1/70
2/70
3/70
7/70
8/70
9/7.0
10/70
1/71
2/71
3/71
4/71
5/71
6/71
8/71
9/71
10/71
11/71
1/72
4/72
9/72
12/72
1/73
2/73
3/73
4/73
5/73
6/73
7/73
EERF
Value
65
37
42
62
68
61
82
54
42
42
41
43
41
64
38
78
24
98
116
57
5
4
126
NR
114
153
126
117
Known
Value
66
35*
41*
58
60*
60*
84
54
43*
41*
38
40*
36*
65*
38*
78
24*
104
113
61
3
3
124
121
116
152
123
116
R
0.99
1.06
1.02
1.07
1.13
1.02
0.98
1.00
0.98
1.02
1.08
1.08
1.14
0.99
1.00
1.00
1.00
0.94
1.03
0.93
1.02
0.98
1.01
1.02
1.01
Date
137Cs
8/73
9/73
11/73
12/73
2/74
4/74
7/74
9/74
11/74
1/75
3/75
5/75
7/75
9/75
11/75
1/76
3/76
5/76
7/76
9/76
11/76
1/77
3/77
5/77
7/77
9/77
11/77
4/78
EERF
Value
NR
NR
122
104
209
!/ -j
16"Q
132
107
82
53
29
75
103
76
56
28
204
78
28
16
50
33
15
24
54
45
23
Known
Value
122
84
126
101
214
174
155
126
101
75
50
25
70
100
75
50
25
206
75
20
11
40
29
10
19
51
39
23
R
0.97
1.03
0.98
1.01
1.03
1.05
1.06
1.09
1.06
1.16
1.07
1.03
1.01
1.12
1.12
0.99
1.04
1.40
1.45
1.25
1.14
1.50
1.26
1.06
1.15
1.00
12
-------
Table 2. (Cont'd.)
Date
1/70
2/70
3/70
7/70
8/70
9/70
10/70
1/71
2/71
3/71
4/71
5/71
6/71
8/71
9/71
10/71
11/71
1/72
2/72
3/72
4/72
9/72
12/72
1/73
2/73
3/73
4/73
5/73
6/73
EERF
Value
0
48
3
62
1
0
1
3
7
3
55
3
2
4
5
103
3
5
6
0
225
2
2
90
5
NR
6
2
4
Known
Value R
0
47 1.02
0
58 1.07
0
0
0
0
0
0
56 0.98
0
0
0
0
96 1.07
0
o
0
0
213 1.06
0
0
93 0.97
0
0
0
0
0
Date
li+0Ba
7/73
8/73
9/73
11/73
12/73
2/74
4/74
7/74
9/74
11/74
1/75
3/75
5/75
7/75
9/75
11/75
1/76
3/76
5/76
7/76
9/76
11/76
1/77
3/77
5/77
7/77
9/77
11/77
4/78
EERF
Value
163
NR
NR
3
ND
170
1
ND
179
ND
ND
ND
ND
ND
140
< 10
ND
< 10
110
< 10
93
< 10
96
< 10
73
< 10
55
< 10
< 10
Known
Value R
148 1.10
152
146
0
0
159 1.07
0
0
193 0.93
0
0
0
0
o
122 1.15
0
0
0
102 1.08
0
85 1.09
0
101 0.95
0
72 1.01
0
50 1.10
0
0
13
-------
Table 2. (Cont'd. )
Date
1/70
2/70
3/70
7/70
8/70
9/70
10/70
1/71
2/71
3/71
4/71
5/71
8/71
9/71
11/71
1/72
2/72
3/72
9/72
12/72
1/73
2/73
3/73
4/73
5/73
6/73
7/73
8/73
EERF
Value
1680
1500
1530
1440
1490
1470
1530
1470
1480
1460
1540
1480
1460
1460
1620
1400
1450
1430
1340
1503
1430
1430
NR
1407
1440
1656
1630
NR
Known
Value
1550*
1465*
1486*
1428*
1469*
1457*
1495*
1510*
1523*
1510*
1482*
1527*
1475*
1496*
1511*
1574*
1529*
1539*
NR
1537*
1473*
NR
1540
1510
1540
1540
1540
1417
R
1.08
1.02
1.03
1.01
1.01
1 .01
0.98
0.97
0.97
0.97
1.04
0.97
0.99
0.98
1.07
0.89
0.95
0.93
0.98
0.97
0.93
0.94
1.08
1.06
_
Date
K**
9/73
11/73
12/73
2/74
4/74
7/74
9/74
11/74
1/75
3/75
5/75
7/75
9/75
11/75
1/76
3/76
5/76
7/76
9/76
11/76
1/77
3/77
5/77
7/77
9/77
11/77
4/78
EERF
Value
NR
1560
1537
1540
1490
1493
1500
1500
1507
1520
1497
1517
1527
1490
1450
1527
1527
1473
1463
1410
1610
1527
1590
1657
1593
1587
1517
Known
Value
1467
1570
1540
1568
1624
1548
1481
1495
1510
1514
1514
1473
1544
1549
1561
1529
1553
1550
1540
1510
1550
1550
1560
1600
1630
1540
1500
R
0.99
1.00
0.98
0.92
0.96
1.01
1 .00
1.00
1.00
0.99
1.03
0.99
0.96
0.93
1.00
0.98
0.95
0.95
0.93
1.04
0.99
1.02
1.04
0.98
1.03
1.01
* Known value not provided - mean of reported concentrations listed
** Units are mg/liter
ND Not detected
NR Not reported 14
R EERF value T known value
-------
Table 3. EMSL-LV Food Cross-Check Samples (pCi/kg)
Date
6/70
1/71
4/71
7/71
1/72
9/72
8/73
5/74
8/74
12/74
6/70
1/71
4/71
7/71
1/72
9/72
8/73
8/74
12/74
4/75
6/70
1/71
4/71
7/71
1/72
7/72
8/73
EERF
Value
20
0
0
10
0
0
NR
91
135
178
25
39
11
9.7
61
27
NR
210
185
157
110
13
24
18
88
98
NR
Known
Value
25
0
0
12
0
0
76
53
204
180
23
42
12
9.3
66
29
112
198
175
150
108
14
21
16
88
93
107
R
0.85
0.83
1.71
0.66
0.99
1.09
0.93
0.92
1.04
0.92
0.93
1.06
1.06
1.05
1.02
0.93
1.14
1.12
1.00
1.05
Date
89Sr
4/75
12/75
4/76
8/76
11/76
2/77
5/77
8/77
11/77
3/78
90Sr
12/75
4/76
8/76
11/76
2/77
5/77
8/77
11/77
3/78
131!
4/75
4/76
8/76
11/76
2/77
5/77
8/77
1
EERF
Value
0
95
NR
NR
87
NR
28
14
38
< 5
146
NR
54
107
59
21
19
24
37
144
NR
141
< 10
79
< 10
63
* ' - ^
Known
Value
0
124
101
82
114
43
26
18
49
0
125
0
41
96
55
26
12
20
31
149 .
0
152
0
81
0
65
R
0.77
0.76
1.08
0.78
0.78
1.17
1.32
1.11
1.07
0.81
1.58
1.20
1.19
0.97
0.93
0.98
0.97
15
-------
Table 3. (Cont'd.)
Date
5/74
8/74
12/74
6/70
1/71
4/71
7/71
9/72
8/73
5/74
8/74
12/74
6/70
1/71
4/71
7/71
1/72
7/72
8/73
5/74
8/74
12/74
6/70
1/71
4/71
EERF
Value
56
215
243
45
61
22
19
88
NR
71
206
177
0
0
25
2
1
1
NR
ND
177
ND
1570
1490
1460
Known
Value
47
216
175
43
60
20
16
98
85
65
205
176
0
0
27
0
0
0
125
0
207
0
1583*
1513*
1477*
R
1.19
1.00
1.39
1.05
1.02
1.10
1.19
0.90
1.09
1.00
1.01
0.93
0.86
0.99
0.99
0.99
Date
131!
11/77
3/78
137Cs
4/75
8/76
11/76
2/77
5/77
8/77
11/77
3/78
^"Ba
4/75
12/75
4/76
8/76
2/77
5/77
8/77
11/77
3/78
K**
4/75
8/76
11/76
16
EERF
Value
< 10
68
148
36
55
47
19
15
26
34
< 10
ND
NR
246
< 10
< 10
51
< 10
< 10
1887
2387
2517
Known
Value
0
74
150
31
46
45
20
16
20
41
0
0
150
226
0
0
50
0
0
2216
2660
2745
R
0.92
0.99
1.16
1.20
1.04
0.95
0.94
1.30
0.83
1.09
1.02
0.85
0.90
0.92
-------
Table 3. (Cont'd.)
Date
7/71
1/72
8/73
5/74
8/74
12/74
EERF
Value
1570
1570
NR
2194
2290
2427
Known
Value
1580*
1568*
1435
2330
2389
2619
R
0.99
1.00
0.94
0.96
0.93
Date
2/77
5/77
8/77
11/77
3/78
EERF
Value
2537
2477
2520
2473
2720
Known
Value
2670
2660
2670
2620
2930
R
0.95
0.93
0.94
0.94
0.93
* Known value not provided - mean of reported concentrations listed
** Units are mg/kg
ND Not detected
NR Not reported
R EERF value -r known value
17
-------
Table 4. EMSL-LV Soil Cross-Check Samples (pCI/kg)
Date
10/70
2/71
6/71
10/70
2/71
10/70
10/70
2/71
6/71
12/70
12/70
12/70
2/71
2/71
4/71
4/71
EERF
Value
617
862
240
1592
1958
454
912
2200
196
0.50
0.34
15.8
2.43
ND
1.62
0.32
Known
Value
745
982
215
1803
1960
589
1016
2460
151
0.47
0.26
15.7
2.24
0.04
1.74*
0.18*
R
0.83
0.88
1.12
0.88
1.00
0.77
0.90
0.89
1.30
1.06
1.30
1.01
1.09
0.93
1.78
Date
60Co
2/72
6/72
io6Ru
6/71
2/72
137Cs
2/72
6/72
239pu**
5/71
5/71
6/71
6/72
5/77
5/78
EERF
Value
1131
1019
382
960
937
1424
0.19
ND
21.0
3.0
0.36
3.41
Known
Value
1031
1214
315
2054
989
1601
0.21
0.004
18.2*
3.3
0.41
4.05
R
1.10
0.84
1.21
0.47
0.95
0.89
0.91
1 .15
0.91
0.88
0.84
* Known value not provided - mean of reported concentrations listed
** Units are pCi/g
ND Not detected
R EERF value -f known value
18
-------
Date
2/71
4/71
6/71
8/71
R EERF
Date
10/70
3/72
4/72
7/72
4/74
3/78
EERF Known
Value Value
3.0 3.7
1.3 1.2
1.0 1.1
3.0 2.7
value v known value
Table 6. Some
Sample Nuclide
Type
Soil ^^Ce
Water 58Co
Sea
Water 239Pu
Water ^Ce
Air
Filter 230Th
Water 228Ra
Date
R
239pu
0.81 12/71
1.08 2/72
0.91 8/72
1.11
Non-Routine EMSL-LV
EERF
Value
730 pCi/kg
328 pCi/£
1.8 pCiA
540 pCi/£
9 pCi
15.2 pCi/£
EERF Known
Value Value
0.78 0.82
2.3 1.6
5.8 6.5
Cross-Check Sampl
Known
Value
1074 pCi/kg 0
322 pCi/£ 1
1.8 pCi/£ 1
487 pCi/£ 1
15 pCi 0
16.7 pCi/£ 0
R
0.95
1.44
0.89
es
R
.68
.02
.00
.11
.60
.91
R EERF value -f known value
19
-------
the known Reference Center values yielding a ratio, R. The magnitude by which R differs
from unity is a measure of agreement. These ratios are also given in the tables for each
analysis.
These results are summarized for each sample type in tables 7 thru 10. The
radionuclide is given in the first column with the number of samples shown in
parentheses. Then given are the ranges in the values of R followed by the percent of
analyses falling within ± 10%, ± 20% and those differing by more than ± 20% of the
known Reference Center value. Agreement within ± 10% is considered very good while
those within ± 20% are considered satisfactory.
Unspiked samples (zero concentration) were not included in the summary tables, 7
thru 10. In the absence of added radioactivity, the concentrations were often reported as
ND (not detectable), zero or as a small value, often smaller than the minimum detectable
level (MDL) of the method used. The actual MDL's attained for the radionuclides in these
type samples are listed in table II, and these values should have been used whenever
appropriate.
This laboratory's results usually compared satisfactorily with the known
concentrations. Ninety percent of the results of all 748 analyses reported were within ±
20% of the Reference Center value. In general, only the gross alpha activities in water and
the 89Sr concentrations in milk and food are of concern. Inconsistencies in the 89Sr values
were traced to incorrect counting efficiency factors. Erroneous gross alpha values were
due to self-absorption linked to differences in the Reference Center spike and the 239Pu
standard used in this laboratory. A natural uranium standard is now being used which
appears to be more congruous with the spike.
III. Participation in the WHO and IAEA Intercomparison Programs
While participating in the EMSL-LV intercomparison program, the EERF
simultaneously participated in similar programs conducted by the World Health
Organization (WHO) and the International.Atomic Energy Agency (IAEA), although on a
more limited basis. Intercomparison results for samples distributed by the WHO are
available only for 1976 and 1977, while results are available back to 1973 for the IAEA
samples. The intercomparison results for samples provided by these two Reference
Centers are given in tables 12 and 13.
Agreement of our results with those provided by the two International Reference
Centers was somewhat less than that for the EMSL-LV program. For the WHO samples,
the EERF concentration is compared to an International Reference Center (IRC) value,
while a "true" value was supplied by the IAEA for about one-half of their intercomparison
samples. For samples not supplied with a "true" concentration, our results are compared
to the average value obtained by all participating laboratories after outliers were
eliminated using the Chauvenet's Test. The EERF reported concentrations agreed within
± 20% of the provided concentration for about 80% of the samples analyzed. Some of the
discrepancies were readily apparent. The large discrepancies associated with the 137Cs
value reported in the WHO surface water sample for June 1976 and the 106Ru value
reported in the IAEA marine sediment for January 1973 were attributed to computational
errors, while the excessive stable strontium concentration reported in the two WHO bone
samples in March 1977 was believed due to contamination. A reanalysis of the latter
samples yielded concentrations of 147 M g/g and 177 M g/g for samples 1 and 2,
respectively, which is within about ± 10% of the IRC value.
20
-------
Table 7. Summary of EMSL-LV Water Cross-Check Samples
Nuclide
3H (44)*
51Cr ( 4)
60Co (19)
65Zn (16)
89Sr (12)
90Sr (13)
106Ru (16)
13ttCs (18)
137Cs (16)
226Ra (29)
239Pu ( 2)
Alpha (33)
Beta (35)
Range
in R
0.92-1.27
0.86-1.13
0.85-1.11
0.86-1.14
0.68-1.00
0.90-1.16
0.71-1.11
0.88-1.11
0.93-1.42
0.97-1.22
0.94-0.97
0.26-1.10
0.75-1.57
* Number of cross-check samples is given in
Table 8.
Nuclide
89Sr (28)*
90Sr (50)
131I (42)
137Cs (51)
llt0Ba (15)
K (32)
Summary of EMSL-LV Milk
Range
in R
0.67-1.30
0.77-1.40
0.83-1.15
0.93-1.50
0.93-1.15
0.92-1 .08
Percent of
from R = 1 .
< 10% <
87
25
79
81
33
77
69
89
69
73
100
15
54
parentheses.
Cross-Check
Percent of
from R = 1 .
< 10% <
36
70
91
76
80
100
values di
00 by:
20%
96
100
100.
100
83
100
94
100
94
97
100
54
74
Samples
values di
00 by:
20%
68
92
100
90
100
100
ffering
> 20%
4
0
0
0
17
0
6
0
6
3
0
46
26
ffering
> 20%
32
8
0
10
0
0
* Number of cross-check samples is given in parentheses.
21
-------
Table 9. Summary of EMSL-LV Food Cross-Check Samples
Nuclide Range
in R
89Sr (10)* 0.66-1.71
90Sr (17) 0.81-1.58
131I (14) 0.92-1.39
137Cs (16) 0.83-1.30
140Ba ( 4) 0.86-1.09
K (16) 0.85-1.00
* Number of cross-check samples is given
Table 10. Summary of EMSL-LV Soil and
Nuclide Sample Range
Type in R
60Co ( 5)* Soil 0.83-1.19
106Ru ( 4) Soil 0.47-1.21
131*Cs ( 1 ) Soil
137Cs ( 5) Soil 0.89-1.30
239Pu (11) Soil 0.84-1.30
239Pu ( 7) Air Filter 0.81-1.44
Percent of
from R = 1 .
< 10% <
20
59
72
56
75
87
in parentheses
values differing
00 by:
20%
40
88
93
94
100
100
Air Filter Cross-Check
Percent of
from R = 1 .
< 10% <
0
25
0
20
55
43
values di
00 by:
20%
100
50
0
80
82
86
> 20%
60
12
7
6
0
0
-
Samples
ffering
> 20%
0
50
100
20
18
14
* Number of cross-check samples is given in parentheses.
22
-------
Table 11. Minimum Detectable Concentration for Routine Cross-Check
Sample Analyses
Water Samples (pCi/A)
3H - 200 90Sr - 1 228Ra 1
51Cr - 30 105Ru - 30 239Pu - 0.015
60Co - 10 134Cs 10 Gross alpha - 2
65Zn - 20 137Cs - 10 Gross beta - 1
89Sr - 5 226Ra - 0.1
Milk (pCi/A) and Food (pCi/kg) Samples
89Sr - 5 137Cs - 10
90Sr 1 llt0Ba - 10
131I - 10
Soil Samples (pCi/g)
60Co - 0.010 137Cs - 0.010
10GRu - 0.030 239Pu - 0.015
13"Cs - 0.010
23
-------
Table 12. WHO Intercomparison Samples
Nucl ide
3H
3H
226Ra
Gross beta
3H
90Sr
95Zr+95Nb
103Ru
90Sr
137Cs
90Sr
C^c)
EERF IRC , » Nucl ide
Value Valueiaj R
703
4050
14.
32
2400
38
0
0
9
15
Sampl
8.
360
370
Rainwater (pCi/Jl) January 1
960 0.73
Rainwater (pCi/£) February
4000 1.01
Mineral Water (pCi/£) March
,3 13.7 1.04 Nat. U^
63 0.51 K(c)
Surface Water (pCi/fc) June 1
2500 0.96 125Sb
36 1.06 131+Cs
< 1.7 --- 137Cs
< 6 --- 106Ru+106Rh
Liquid Milk (pCi/£) September
11 0.82 Ca^d^
12 1.25 K(d)
Animal Bone (pCi/g ash) March
e 1
6 8.3 1.04 90Sr
156 2.31 Sr(b)
384 0.96 Ca^c)
EERF
Value
975
1975
1976
16.7
18
976
75
0
17
328
1976
1.10
1.13
1977
Sample 2
2.7
393
380
IRC ,
Value13
19.4
22
67
< 4
8
320
1.14
1.44
2.7
198
388
) R
0.86
0.82
1.12
2.12
1.03
0.97
0.90
1.00
1.99
0.98
Sea Fish (pCi/g dry) May 1977
90Sr
is^s
137Cs
0.
0.
3.
13 0.16 0.81 Ca^C^
37 0.37 1.00 K^C)
9 3.7 1.05 Sr^
47
13
180
44
12.3
190
1.07
1.06
0.95
24
-------
Table 12. (Cont'd.)
Nuclide
EERF
Value
IRC
Val
ue(a
) R
Nuclide EERF IRC , v
Value Va1ueUJ
R
Marine Sediment (pCi/g dry) August 1977
90Sr
106Ru+106Rh
137Cs
i^Ce+^Pr
90Sr
137Cs
0.
6.
0.
4.
15
32
15 0.
5 6.
17 0.
4 4.
Liqui
16
31
21
4
19
3
d Mi
0.71
1.02
0.90
1.02
95Zr+95Nb
125Sb
13"Cs
0
0
0
.47
.9
.06
0
0
0
.46
.10
.05
1
0
1
.02
.90
.20
Ik (pCi/£) March 1978
0.94
1.03
Ca(d)
K(d)
1
1
.15
.52
1
1
.13
.48
1
1
.02
.03
a) International Reference Center (IRC) value
b) Units are yg/£ or yg/g
c) Units are mg/H or mg/g
d) Units are
25
-------
Table 13. IAEA Intercomparison Samples
Nuclide
90Sr
106Ru
137Cs
90Sr
106Ru
134Cs
137Cs
1Mt'Ce
239Pu
Nuclide
U(c)
Th
137Cs
89Sr
90Sr
EERF Average, , Nuclide EERF Average/ »
Value Value (a> R Value Value (a)
Marine Sediment (pCi/g dry) January 1973
13.2 13.8(23)(b) 0.96 11MfCe 279 126 (33)
44 88 (34) 0.50 238Pu 0.045 0.042(14)
15 10 (27) 1.50 239Pu 1.06 0.96 (18)
373 356 (38) 1.05
Marine Animals (pCi/g) January 1975
Sample 1 Sample 2
NR(d) 7.4(18) 6°Co 133 166 (23)
2.4 4.3(13) 0.56 90Sr NR 0.25 (11)
0.3 0.29(7) 1.03 134Cs 0.9 1.0 (7)
15.5 16.2(23) 0.96 137Cs 4.0 4.3 (22)
6.1 2.7(13) 2.26 141tCe NR 27 (3)
8.2 11 (5) 0.75 "°K 11.7 11 (5)
Seaweed (pCi/g) November 1977
26 27 (17) 0.96
EERF True , , Nuclide EERF True , ,
Value Valuelej R Value ValueleJ
Human Urine (pCi'A) November 1973
28 33.6 0.83 239Pu 0.65 0.63
22 11.2 1.96
Water (pCiA) November 1973
Sample 1 Sample 2
9.6 9.5 1.01 90Sr 888 - 940
1,938 1,930 1.00 137Cs 185,200 191,000
Milk (pCiA) May 1976
1,495 1,400 1.07 137Cs 2,116 2,140
486 490 0.99
26
R
2.21
1 .07
1.10
0.80
0.90
0.93
1.06
R
1.03
0.95
0.97
0.99
-------
Table 13. (Cont'd.)
Nuclide
3H
60Co
90Sr
137Cs
226Ra
239PU
EERF
Value
Sample
3,630 2,
34
4.9
7.5
3.40
2.93
Sample
True ,
Value16
Water
1
540
51.5
3.55
8.15
3.64
3.21
Water
1
v Nuclide
> R
(pCi/ji) January 1
1.43 3H
0.66 60Co
1.36 90Sr
0.92 137Cs
0.93 226Ra
0.91 239Pu
(pCi/£) November 1
EERF
Value
977
Sample
74,030
2,100
62
111
42.6
52.0
977
Sample
True / x
Valuelej
2
45,300
2,530
52.0
119
53.3
47.0
2
R
1.63
0.83
1.19
0.93
0.80
1.11
Ra 0.15 0.15 1.00 226Ra 683 600 1.14
a) Average concentration of reported values computed from results accepted by
the Chauvenet's test
b) Number of reported values used to compute mean concentration is given in
parentheses
c) Units are ug/£
d) NR - not reported
e) True value - reported by IAEA as "true" concentration
27
-------
IV. Summary
This report compiles all available results of the EERF's participation in
interlaboratory comparison programs. In general the results are satisfactory, although
there are some areas of concern. A summary of all analyses for the predominant
radionuclides included in this report is presented in table 14. Also included are the results
reported for unspiked samples. Results for the unspiked samples reported as not
detectable (ND), zero, or as a value less than the assigned minimum detectable level
(MDL) given in table 11 were considered to agree within ±10%; a value reported as
greater than the MDL was considered unsatisfactory. For the 753 specific radionuclide
analyses, 75% and 92% were measured within ± 10% and ± 20%, respectively, of the
Reference Center values.
These data are presented graphically in figure 1, where the cumulative probability is
plotted with the observed percent error in increments of 5%. This presentation of the data
may better illustrate the EERF's overall performance in the three intercomparison
programs. The probability that the result of an analysis will be within a selected error of
the true concentration can be easily ascertained from the graph. For example, the
probability that the result of an analysis will be within 25% of the true concentration is
seen to be 0.94. These data were also compared by year, and no trend with time was
evident.
The most important function of intercomparison programs is to identify problem
areas. If a problem exists, immediate remedial action should be initiated. As is apparent in
the results reported, errors can occur for numerous reasons; improperly following a
tested procedure, arithmetical errors in the calculations, permitting contamination to
enter the sample during analysis, undetected fluctuations in counting efficiencies,
backgrounds, etc., and using incorrect weights, absorption factors, etc. Continual
alertness and expedient action to recognize and correct these problems should be a basic
requirement of any analytical chemistry laboratory.
It is the intent of the EERF to issue brief biannual reports similar to this which will
present the results of our continuing participation in intercomparison programs.
28
-------
Table 14. Summary of Comparability of Specific Isotope Analyses
Isotope
3H
89Sr
90Sr
226Ra
238/239pu
Gamma emitters
K
Ca-Sr
Notes:
, 1 ) Analyses
included.
2) Unspiked
Percent of values differing Number of
from R = 1 .00 by: Analyses
< 10% <
80
56
68
70
57
79
92
75
of samples from
samples reported
20%
92
78
90
97
86
94
99
75
all
by
> 20%
8
22
10
3
14
6
1
25
three reference centers
EERF as 0, a less-than
49
78
95
33
28
390
72
8
are
value
or a value less than the MDL listed in Table 11 are assigned
to the < 10% category; values reported greater than the MDL
listed in Table 11 are assigned to the > 20% category.
3) Concentrations reported within ± 20% of the known concentration
are considered satisfactory.
29
-------
CO
o
1.00
0.8
>. 0.6
3
03
o
a
| I |.« v-v.v.v .-.-..'.. [[[x.
0.4
o
0.2
5 10 15 20 25 30 35 40 45 50 55 60
Percent Error
-------
REFERENCES
1. HARLEY, J. "Experience with an Analytical Quality Control Program," ASTM
Conference on Effluent and Environmental Radiation Surveillance, Johnson, VT,
July 1978.
2. WELFORD, G. A. and HARLEY, J. H. "HASL Participation in IAEA Intercomparisons,"
Energy Research and Development Administration Report, HASL-322, June 1977.
31
-------
ACKNOWLEDGEMENTS
It is not possible to give adequate credit to all those who have been involved in these
programs during the past 8 years, but a number who have participated, principally the
chemists and laboratory technicians, are listed below:
Leslie Bankert Gerry Luster Mark Semler
Imogene Brooks Evelyn Palmer Albert Smith
Susan Baker Edward Raabe Helen Wilson
Avis Culver
The authors also appreciate the helpful suggestions of Charles R. Phillips and Jon A.
Broadway during the preparation of this report and the effort required of Annette B. Fannin to
type the many tables.
* G PO 1979-642.648 / 633O. REGION NO
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